[Whyman]

Fairly simple, part fill your water carrier and add some sterilising solution to the required strength and then fill the water pipes of the caravan using the pump. Bleed all of the air out of the system.

Leave the solution in for the time specified and then flush out with clean water.

I also use a Floe drain down kit after each use and particular when winterising the van to get all the stale water out and prevent any frost damage during the winter.